Sunday, February 5, 2012

The race flow chart and terrain challenges

As I've mentioned in earlier posts, I'm fascinated by the Trackleaders race flow chart and think it might be one of the handiest tools for understanding what's going on on the trail. So, I thought I'd take a look at what happened around a challenging bit of terrain.

Everybody knows that Eagle Summit can be extremely difficult. Rosebud gets less press, but it's very difficult, as well. At the mushers' meeting the mushers were warned about it, and veterans warned rookies outside the meeting. Rosebud is early in the race, at about mile 90 according to the trackleaders track. So, here's what the race flow chart showed:

To provide a little more background, the x-axis is the time on the race clock -- how many hours we are into the race. The y-axis is the miles traveled. What this means is that when a team is stopped the line is perfectly horizontal (flat), and the steeper the line is the faster the team is traveling. Also, because the plot shows us where people were at what time on the race clock we can understand where they really were in relation to one another. When lines cross, that's a pass. If the lines look like they've merged, the teams are traveling together. When the line goes perfectly vertical a team is traveling infinitely fast (and from what I saw in the staging area yesterday, we could possibly see Jake Berkowitz's line do this). In this screen grab you can see everybody's lines go flat at about mile 113 - that's the mile 101 checkpoint. As I said, fantastic tool.

So, what happened at Rosebud? Well, one of the things we see is that Mike Ellis's and Kristy Berington's lines go flat at about race mile 89, and they stay flat for about an hour. Mike said he was going to camp for a bit before going over so it's a little surprising it's not a longer stop, but not that surprising. Then at about 15:15 on the race clock (the "time" axis shows decimal fractions, so "15.5" is 15 hours and 30 minutes) they start moving, with Mike leading. Again, not a surprise -- Mike is a veteran and knows the trail. Then they stop again for about 20 minutes on the other side before moving along. It looks like Brent also took a break at about mile 89 before climbing Rosebud, without stopping on the other side.

Another interesting thing that was going on was that Kyla Durham was stopping often, and for short periods.

The front of the pack is going over Eagle Summit as I write this, and I am sure that the race flow chart is going to be fascinating. Some mushers stop at the top to rest their dogs or to put rough locks on their runners, while others feel that the best way to deal with the precipitous drop on the downhill side is to just go for it and not give the dogs a chance to get perky again. Here's a chance to find out who's in which corner.